THE alleged distributors of a deadly drug linked to Australia's first "bath salts" death have been arrested after raids of about 20 businesses and homes in southeast Queensland.

The major police operation on Wednesday hit adult shops, tobacconists, alternative stores and homes selling the synthetic drugs - which are named "bath salts" due to the labelling on packaging used by suppliers to try to fool authorities when importing the drugs or moving them between states.

About 4.2kg of synthetic drugs sold as "legal highs" with a street value of $147,000 were seized in the raids as well as $120,000 worth of property including computers, phones a 4WD and a sedan.

An Ormeau couple were arrested with boxes of the drugs.

Police will allege they have distributed the drug - also labelled as "Smokin' Slurrie" - to stores across Queensland, and an adult store near Newcastle in NSW where truck driver Glenn Punch bought "bath salts". He died after injecting it.

Punch's girlfriend Rachael Hickel said the couple paid $150 for the "Smokin' Slurrie" drugs. The pair had gone into a deep psychosis and had both taken off their clothes.

It is understood a man whose name was on boxes of the drugs seized in Queensland was also being interviewed in NSW last night.

Police believe the drug contains Alpha-PVP (Alpha-Pyrrolidinovalerophenone), with symptoms described as being similar to the deadly designer drug MDPV (Methylenedioxypyrovalerone).

In a separate case, a Mackay man had his leg amputated after consuming large amounts of the drugs.

The shutdown of sales of the drugs including synthetic cocaine, marijuana and pills sold as "legal highs" comes just days before Schoolies Week kicks off.

State Drug Investigation Unit Detective Superintendent Steve Holahan said: "We're targeting a fairly ongoing distribution network for these stores; we're also looking at online sales and marketing of these drugs.

"We've got some anecdotal evidence about some of the harms and irrational behaviour that these substances are having, particularly on young people."

Det Supt Holahan said there were no suspected links to outlaw motorcycle gangs.